U.S. patent application number 12/630834 was filed with the patent office on 2010-06-17 for lamp.
Invention is credited to Hiroyuki CHIKAMA, Nao NAKANO.
Application Number | 20100149803 12/630834 |
Document ID | / |
Family ID | 42240284 |
Filed Date | 2010-06-17 |
United States Patent
Application |
20100149803 |
Kind Code |
A1 |
NAKANO; Nao ; et
al. |
June 17, 2010 |
LAMP
Abstract
A lamp can includes: a first reflective surface which can be
provided on a surface of a circular shaped member, a radius of a
top of the annular member can be longer than a radius of a bottom
of the annular member; a second reflective surface which can be
arranged inside of the first reflective surface and can have a
conical shape, a vertex of the second reflective surface can be
directed to a top side of the first reflective surface; and a
plurality of light emitters which can be annularly arranged on the
first reflective surface around the second reflective surface at a
predetermined interval so as to be projected on the second
reflective surface.
Inventors: |
NAKANO; Nao; (Tokyo, JP)
; CHIKAMA; Hiroyuki; (Tokyo, JP) |
Correspondence
Address: |
CERMAK KENEALY VAIDYA & NAKAJIMA LLP
515 EAST BRADDOCK RD SUITE B
Alexandria
VA
22314
US
|
Family ID: |
42240284 |
Appl. No.: |
12/630834 |
Filed: |
December 3, 2009 |
Current U.S.
Class: |
362/235 |
Current CPC
Class: |
F21S 43/14 20180101;
F21S 43/30 20180101; F21S 43/40 20180101 |
Class at
Publication: |
362/235 |
International
Class: |
F21V 7/00 20060101
F21V007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 11, 2008 |
JP |
2008-316045 |
Claims
1. A lamp comprising: a first reflective surface located on a
surface of an annular shaped member, a radius of a top of the
annular shaped member being longer than a radius of a bottom of the
annular shaped member; a second reflective surface located inside
of the first reflective surface and having a conical shape, a
vertex of the second reflective surface being directed to the top
of the first reflective surface; and a plurality of light emitters
annularly arranged on the first reflective surface around the
second reflective surface at a predetermined interval and arranged
to project light on the second reflective surface.
2. The lamp according to claim 1, wherein the first reflective
surface is one of a flat surface and a concave surface; the flat
surface is a straight line in a cross-section view of the flat
surface taken along a lamp optical axis and passing through the
vertex of the second reflective surface; and, the concave surface
is a curved line in a cross-section view of the concave surface
taken along the lamp optical axis and the curved line being concave
inward with respect to a center of the lamp.
3. The lamp according to claim 1, wherein the second reflective
surface is one of a flat surface and a convex surface; the flat
surface is a straight line in a cross-section view of the flat
surface taken along a lamp optical axis passing through the vertex
of the second reflective surface; and the convex surface is a
curved line in a cross-section view of the convex surface taken
along the lamp optical axis and the curved line being convex
outward with respect to a center of the lamp.
4. The lamp according to claim 1, wherein each of the plurality of
light emitters comprises: a lens which is set in an aperture on the
first reflective surface; a first light source which corresponds to
the lens, and is arranged at a back side of the first reflective
surface; and a third reflective surface which corresponds to the
lens, is arranged adjacent to the back side of the first reflective
surface, and is configured to reflect light irradiated from the
first light source toward the second reflective surface.
5. The lamp according to claim 4, wherein the lens includes a first
end portion having an acute angle, and a second end portion on an
opposite side with respect to the first end portion, and the first
end portion is located closer to the top of the first reflective
surface, and the second end portion is located closer to a bottom
of the first reflective surface.
6. The lamp according to claim 4, wherein the first light source is
configured to irradiate light outwardly with respect to a center of
the lamp.
7. The lamp according to claim 4, wherein the first light source is
an LED light source.
8. The lamp according to claim 4, further comprising a plurality of
fourth reflective surfaces each of which corresponds to a
respective one of the first light sources, is arranged adjacent to
the back side of the first reflective surface, and is configured to
reflect light irradiated from the respective first light source and
to direct the light along a lamp optical axis.
9. The lamp according to claim 1, further comprising: a plurality
of second light sources adjacent to a back side of the second
reflective surface; and a plurality of fifth reflective surfaces
each of which corresponds to a respective one of the second light
sources, is arranged adjacent to the back side of the second
reflective surface, and reflects light irradiated from the
respective second light source to direct the light along a lamp
optical axis, wherein the second reflective surface is configured
to transmit light incident on the back side thereof.
10. The lamp according to claim 9, wherein the second light sources
are annularly arranged around the lamp optical axis at a
predetermined interval, and irradiate light inwardly with respect
to a center of the lamp.
11. A lamp having an optical axis, comprising: a first annular
reflector having an outer perimeter, a front surface extending at
an angle relative to the optical axis and a back surface opposite
to the front surface; a second reflector located within the outer
perimeter of the first annular reflector and having a convex
surface facing the first annular reflector, the second reflector
including a vertex adjacent to the optical axis and the second
reflector extending between the optical axis and the front surface
of the first annular reflector; and a first plurality of
semiconductor light emitters adjacent to at least one of the front
surface and the back surface of the first annular reflector, spaced
annularly about the optical axis, and configured to project light
onto the convex surface of the second reflector.
12. The lamp according to claim 11, wherein the front surface of
the first annular reflector abuts the convex surface of the second
reflector.
13. The lamp according to claim 11, wherein the convex surface is
one of conical and polygonal pyramidal.
14. The lamp according to claim 13, wherein the convex surface
appears as an outwardly curved line when viewed in a
cross-sectional plane that includes the optical axis and the
vertex.
15. The lamp according to claim 11, wherein each of the light
emitters includes an LED light source adjacent to the front surface
of the first reflector such that an image of the LED light source
is reflected in the convex surface.
16. The lamp according to claim 11, wherein each of the light
emitters includes: an LED light source adjacent to the back surface
of the first reflector; and a lens adjacent to the front surface of
the first reflector such that an image of the lens is reflected in
the convex surface.
17. The lamp according to claim 16, further comprising: a third
reflector positioned such that the back surface of the first
reflector lies intermediate the front surface of the first
reflector and the third reflector; and wherein each of the LED
light sources is configured to emit light toward the third
reflector.
18. The lamp according to claim 17, wherein the third reflector
includes a first plurality of reflector surfaces and a second
plurality of reflector surfaces, each of the LED light sources
corresponding to one of the first plurality of reflector surfaces
and the second plurality of reflector surfaces, wherein light
emitted from each of the LED light sources and incident on a
respective one of the first plurality of reflector surfaces is
directed substantially parallel with the optical axis, and light
emitted from each of the LED light sources and incident on a
respective one of the second plurality of reflector surfaces is
incident on the convex surface of the second reflector.
19. The lamp according to claim 11, further comprising: a second
plurality of semiconductor light emitters adjacent the back surface
of the first reflector and configured to emit light in a radially
inward direction relative to the optical axis; and a fourth
reflector facing a side of the second reflector that is opposite to
the convex surface relative to the optical axis and including a
fourth plurality of reflective surfaces each corresponding to a
respective one of the second plurality of semiconductor light
emitters, wherein the first plurality of semiconductor light
emitters are configured to emit light in a radially outward
direction relative to the optical axis, and the fourth reflector is
oriented relative to the second plurality of semiconductor light
emitters such that light emitted from the second plurality of
semiconductor light emitters is incident on the fourth reflector
surface and is directed substantially parallel with the optical
axis.
20. The lamp according to claim 19, wherein each of the second
plurality of semiconductor light emitters is located adjacent, and
in a back to back relationship with, a respective one of the first
plurality of semiconductor light emitters, such that each of the
first plurality of semiconductor light emitters has a light
emitting axis that is diametrically opposite to a light emitting
axis of a respective one of the second plurality of semiconductor
light emitters.
Description
[0001] This application claims the priority benefit under 35 U.S.C.
.sctn.119 of Japanese Patent Application No. 2008-316045 filed on
Dec. 11, 2008, which is hereby incorporated in its entirety by
reference.
BACKGROUND
[0002] 1. Technical Field
[0003] The presently disclosed subject matter relates to a lamp,
and more particularly to a lamp having a new light emission
appearance applicable to a vehicle signal lamp, general
illumination other than the vehicle signal lamp, or the like.
[0004] 2. Description of the Related Art
[0005] Conventionally, a vehicle lamp including a convex reflective
surface has been known (for example, see Japanese Patent
Application Laid-Open No. 2002-343111).
[0006] FIG. 18 is a sectional view for illustrating a configuration
of a vehicle lamp described in Japanese Patent Application
Laid-Open No. 2002-343111.
[0007] As shown in FIG. 18, the vehicle lamp 200 described in
Japanese Patent Application Laid-Open No. 2002-343111 includes a
convex reflective surface 210 placed at a center of the lamp 200, a
plurality of LED (Light Emitting Diode) light sources 220 annularly
arranged around the convex reflective surface 210, a front lens
230.
[0008] In the vehicle lamp 200 described in Japanese Patent
Application Laid-Open No. 2002-343111, the convex reflective
surface 210 is formed as a paraboloidal reflective surface obtained
by rotating a parabola C having a focus set near the LED light
source 220 around an optical axis AX. Thus, an irradiation light
from the LED light source 220 having reached the convex reflective
surface 210 is converted into parallel rays by the convex
reflective surface 210, and the rays pass through the front lens
230 and are irradiated in a direction indicated by arrows in FIG.
18.
SUMMARY
[0009] However, in the vehicle lamp 200 described in Japanese
Patent Application Laid-Open No. 2002-343111, as shown in FIG. 18,
the convex reflective surface 210 is a substantially conical
reflective surface with the parabola C, which is a curved line
recessed outwardly, appearing when cut along a plane through a
vertex of the surface 210. Thus, the LED light source 220 is hardly
(or extremely slightly) projected on the convex reflective surface
210. Accordingly, the vehicle lamp 200 described in Japanese Patent
Application Laid-Open No. 2002-343111 has a uniform light emission
appearance of the LED light source 220, and there is a problem that
it is difficult to provide a lamp having a new light emission
appearance.
[0010] The presently described subject matter is achieved in view
of such circumstances, and can include a lamp which forms a pattern
with an appearance changing according to viewpoint positions of an
observer and has a new light emission appearance.
[0011] To achieve this, an aspect of the presently described
subject matter provides a lamp that can include: a first reflective
surface which can be provided on a surface of a circular shaped
member, a radius of a top of the annular member can be longer than
a radius of a bottom of the annular member; a second reflective
surface which can be arranged inside of the first reflective
surface and can have a conical shape, a vertex of the second
reflective surface can be directed to a top side of the first
reflective surface; and a plurality of light emitters which can be
annularly arranged on the first reflective surface around the
second reflective surface at a predetermined interval so as to be
projected on the second reflective surface.
[0012] Another aspect of the presently described subject matter
provides a lamp, wherein the first reflective surface can be formed
as a flat surface, a cross-section view of the flat surface along a
lamp optical axis passing through a vertex of the second reflective
surface can be a straight line, or a concave surface, a
cross-section view of the concave surface along the lamp optical
axis can be a curved line that can be concave inward with respect
to a center thereof.
[0013] Another aspect of the presently described subject matter
provides a lamp, wherein the second reflective surface can be
formed as a flat surface, a cross-section view of the flat surface
along a lamp optical axis passing through a vertex of the second
reflective surface can be a straight line, or a convex surface, a
cross-section view of the convex surface can be a curved line that
can be convex outward with respect to a center thereof.
[0014] The second reflective surface can be formed as the convex
reflective surface with the curved line protruding outwardly, or a
flat surface with the straight line appearing when cut along the
plane through the lamp optical axis. Thus, the plurality of light
emitters can be projected on the second reflective surface, and a
virtual image projected on the second reflective surface can be
enlarged (or not reduced). Therefore, a pattern with an appearance
changing according to viewpoint positions of the observer can be
formed. Specifically, a lamp can be provided which can form a
pattern with an appearance changing according to viewpoint
positions and can have a new light emission appearance.
[0015] Another aspect of the presently described subject matter
provides a lamp, wherein each of the plurality of light emitters
can include: a lens which can be set in an aperture provided on the
first reflective surface; a first light source which can correspond
to the lens, and can be arranged at a back side of the first
reflective surface; and a third reflective surface which can
correspond to the lens, can be arranged at the back side of the
first reflective surface, and can reflect a light irradiated from
the first light source to make the light reach the second
reflective surface.
[0016] Another aspect of the presently described subject matter
provides a lamp, wherein the lens can include a first end portion
which can be acute-angled; and a second end portion which can be on
the opposite side with respect to the first end portion, and can be
arranged so that the first end portion can be located closer to the
top of the first reflective surface, and the second end portion can
be located closer to the bottom of the first reflective
surface.
[0017] The first end portion of the lens can be located closer to
the top of the first reflective surface, and thus the first end
portion can be projected on a tip (at or in vicinity of the vertex)
of the second reflective surface. Thus, a virtual image of the
first end portion having a very sharp shape can be enlarged, and a
pattern with an appearance significantly changing by slight
movement of the eyes of an observer can be formed. Specifically, a
lamp can be provided that can form a pattern with an appearance
significantly changing by slight movement of the viewpoint
position, and can have a new light emission appearance.
[0018] Another aspect of the presently described subject matter
provides a lamp, wherein the first light source can irradiate the
light outwardly with respect to a center of the lamp.
[0019] Another aspect of the presently described subject matter
provides a lamp, wherein the first light source can be an LED light
source.
[0020] The second reflective surface can be formed as the convex
reflective surface with the curved line protruding outwardly or a
flat surface with the straight line appearing when cut along the
plane through the lamp optical axis. Thus, the plurality of lenses
illuminated by a plurality of first light sources (for example, LED
light sources) can be projected on the second reflective surface.
Thus, a virtual image projected on the second reflective surface
can be enlarged (or not reduced), and a pattern with an appearance
changing according to viewpoint positions can be formed.
Specifically, the lamp can be provided which can form a pattern
with an appearance changing according to viewpoint positions and
can have a new light emission appearance.
[0021] The convex reflective surface can be formed as the convex
reflective surface with a curved line protruding outwardly (or a
straight line) appearing when cut along the plane through the
vertex and the lamp optical axis. Thus, the plurality of light
emitters can be projected on the convex reflective surface, a
virtual image projected on the convex reflective surface can be
enlarged (or not reduced), and a pattern with an appearance
changing according to viewpoint positions can be formed.
[0022] Another aspect of the presently described subject matter
provides a lamp that can include a plurality of fourth reflective
surfaces each of which can correspond to the first light source,
can be arranged at the back side of the first reflective surface,
and can reflect the light irradiated from the first light source to
make the light be directed along the lamp optical axis.
[0023] Also, the irradiation light emitted from the first light
source and having reached the fourth reflective surface can be
reflected by the fourth reflective surface and can be irradiated
through the corresponding lens, and can form a first light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp). Also, the irradiation light
emitted from the first light source and having reached the third
reflective surface can be reflected by the third reflective
surface, can pass through the corresponding lens, and can reach the
second reflective surface. The irradiation light having reached the
second reflective surface can be further reflected by the second
reflective surface, and can form a second light distribution
pattern (particularly a light distribution pattern suitable for a
wide vehicle signal lamp enlarged by the convex reflective surface)
superimposed on the first light distribution pattern.
[0024] Specifically, a lamp can be provided which can form a
pattern with an appearance changing according to viewpoint
positions, and can form a predetermined light distribution pattern
(particularly a light distribution pattern suitable for a vehicle
signal lamp) (combination of a new appearance and a predetermined
light distribution pattern).
[0025] The acute-angled first end portion of the lens can be
located closer to the top of the first reflective surface, and thus
the first end portion can be projected on a tip of the second
reflective surface. Thus, a virtual image of the first end portion
having a very sharp shape can be enlarged (or not reduced), and a
pattern with an appearance significantly changing by slight
movement of the viewpoint position can be formed. Specifically, a
lamp can be provided which can form a pattern with an appearance
significantly changing by slight movement of the viewpoint
position, can form a predetermined light distribution pattern
(particularly a light distribution pattern suitable for a vehicle
signal lamp), and can have a new light emission appearance.
[0026] Another aspect of the presently described subject matter
provides a lamp that can include: a plurality of second light
sources which can be arranged at a back side of the second
reflective surface; and a plurality of fifth reflective surfaces
each of which can correspond to the second light sources, can be
arranged at a back side of the second reflective surface, and can
reflect the light irradiated from the second light source to make
the light be directed along the lamp optical axis, wherein the
second reflective surface can transmit the light from the back side
thereof.
[0027] Another aspect of the presently described subject matter
provides a lamp, wherein the second light sources can be annularly
arranged around a lamp optical axis at a predetermined interval,
and can irradiate the light inwardly with respect to a center of
the lamp.
[0028] The second reflective surface can be formed as the
reflective surface through which the reflected light from the fifth
reflective surfaces having reached the second reflective surface
can pass. Thus, the irradiation light emitted from the second light
source and having reached the fifth reflective surface can be
reflected by the fifth reflective surface and irradiated through
the second reflective surface, and can form a third light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp) superimposed on the first and
second light distribution patterns.
[0029] Specifically, the third light distribution pattern formed by
the irradiation light from the second light source can be added to
the first and second light distribution patterns formed by the
irradiation lights from the first light source. Thus, for example,
when these aspects are applied to a tail lamp of a vehicle, the
light sources can be controlled to turn on only the first light
source when a brake of the vehicle is not applied, and to turn on
both the first light source and the second light source when the
brake is applied. Thus, a sufficient amount of light can be ensured
even when the brake is applied, thereby allowing formation of a
light distribution pattern that can satisfy a government
standard.
[0030] According to an aspect of the disclosed subject matter, a
lamp can include a first reflective surface located on a surface of
an annular shaped member, a radius of a top of the annular shaped
member being longer than a radius of a bottom of the annular shaped
member, a second reflective surface located inside of the first
reflective surface and having a conical shape, a vertex of the
second reflective surface being directed to the top of the first
reflective surface. The lamp can include a plurality of light
emitters annularly arranged on the first reflective surface around
the second reflective surface at a predetermined interval and
arranged to project light on the second reflective surface.
[0031] According to another aspect of the disclosed subject matter,
a lamp having an optical axis can include a first annular reflector
having an outer perimeter, a front surface extending at an angle
relative to the optical axis and a back surface opposite to the
front surface. A second reflector can be located within the outer
perimeter of the first annular reflector and can have a convex
surface facing the first annular reflector. The second reflector
can include a vertex adjacent to the optical axis and the second
reflector can extend between the optical axis and the front surface
of the first annular reflector. A first plurality of semiconductor
light emitters can be located adjacent to at least one of the front
surface and the back surface of the first annular reflector, spaced
annularly about the optical axis, and configured to project light
onto the convex surface of the second reflector.
[0032] According to another aspect of the disclosed subject matter,
the front surface of the first annular reflector can abut the
convex surface of the second reflector.
[0033] According to another aspect of the disclosed subject matter,
the convex surface can be either conical or polygonal
pyramidal.
[0034] According to another aspect of the disclosed subject matter,
the convex surface can appear as an outwardly curved line when
viewed in a cross-sectional plane that includes the optical axis
and the vertex.
[0035] According to another aspect of the disclosed subject matter,
each of the light emitters can include an LED light source adjacent
to the front surface of the first reflector such that an image of
the LED light source is reflected in the convex surface.
[0036] According to another aspect of the disclosed subject matter,
each of the light emitters can include an LED light source adjacent
to the back surface of the first reflector, and a lens adjacent to
the front surface of the first reflector such that an image of the
lens is reflected in the convex surface.
[0037] According to another aspect of the disclosed subject matter,
the lamp can include a third reflector positioned such that the
back surface of the first reflector lies intermediate the front
surface of the first reflector and the third reflector. Each of the
LED light sources can be configured to emit light toward the third
reflector.
[0038] According to another aspect of the disclosed subject matter,
the third reflector can include a first plurality of reflector
surfaces and a second plurality of reflector surfaces, each of the
LED light sources corresponding to one of the first plurality of
reflector surfaces and the second plurality of reflector surfaces.
The light emitted from each of the LED light sources and incident
on a respective one of the first plurality of reflector surfaces
can be directed substantially parallel with the optical axis, and
light emitted from each of the LED light sources and incident on a
respective one of the second plurality of reflector surfaces can be
incident on the convex surface of the second reflector.
[0039] According to another aspect of the disclosed subject matter,
the lamp can include a second plurality of semiconductor light
emitters adjacent to the back surface of the first reflector and
configured to emit light in a radially inward direction relative to
the optical axis, and a fourth reflector facing a side of the
second reflector that is opposite to the convex surface relative to
the optical axis. The fourth reflector can include a fourth
plurality of reflective surfaces each corresponding to a respective
one of the second plurality of semiconductor light emitters. The
first plurality of semiconductor light emitters can be configured
to emit light in a radially outward direction relative to the
optical axis. The fourth reflector can be oriented relative to the
second plurality of semiconductor light emitters such that light
emitted from the second plurality of semiconductor light emitters
is incident on the fourth reflector surface and is directed
substantially parallel with the optical axis.
[0040] According to another aspect of the disclosed subject matter,
each of the second plurality of semiconductor light emitters can be
located adjacent, and in a back to back relationship with, a
respective one of the first plurality of semiconductor light
emitters, such that each of the first plurality of semiconductor
light emitters has a light emitting axis that is diametrically
opposite to a light emitting axis of a respective one of the second
plurality of semiconductor light emitters.
[0041] According to the presently described subject matter, a lamp
can be provided which can form a pattern with an appearance
changing according to viewpoint positions and has a new light
emission appearance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The disclosed subject matter of the present application will
now be described in more detail with reference to exemplary
embodiments of the apparatus and method, given by way of example,
and with reference to the accompanying drawings, in which:
[0043] FIG. 1 is a perspective view of a lamp according to an
embodiment of the presently described subject matter;
[0044] FIG. 2 is an exploded perspective view of components of the
lamp shown in FIG. 1;
[0045] FIG. 3 is an enlarged sectional view of the lamp along line
3-3 shown in FIG. 1;
[0046] FIG. 4 illustrates a method of calculating the shape of a
convex reflective surface;
[0047] FIG. 5 illustrates the method of calculating the shape of
the convex reflective surface;
[0048] FIG. 6 illustrates the method of calculating the shape of
the convex reflective surface;
[0049] FIG. 7 illustrates the method of calculating the shape of
the convex reflective surface;
[0050] FIG. 8 is a front view of the lamp shown in FIG. 1, and
shows an example of a pattern formed by a virtual image projected
on a convex reflective surface when viewed from the front of the
lamp;
[0051] FIG. 9 is a perspective view of the lamp shown in FIG. 1,
and shows an example of a pattern formed by the virtual image
projected on the convex reflective surface when diagonally
viewed;
[0052] FIG. 10 is a perspective view of a lamp according to an
another embodiment (Modified Example 1) of the presently described
subject matter;
[0053] FIG. 11 shows an example of a pattern formed by a virtual
image projected on a convex reflective surface of the lamp shown in
FIG. 10;
[0054] FIG. 12 is a perspective view of a lamp according to another
embodiment (Modified Example 2) of the presently described subject
matter;
[0055] FIG. 13 shows an example of a pattern formed by a virtual
image projected on a convex reflective surface of the lamp shown in
FIG. 12;
[0056] FIG. 14 is a perspective view of a lamp according to another
embodiment (Modified Example 2) of the presently described subject
matter;
[0057] FIG. 15 shows an example of a pattern formed by a virtual
image projected on a convex reflective surface of the lamp shown in
FIG. 14;
[0058] FIG. 16 is a perspective view of the lamp according to the
another embodiment (Modified Example 3) of the presently described
subject matter;
[0059] FIG. 17 is an enlarged sectional view of a lamp along line
17-17 shown in FIG. 16; and
[0060] FIG. 18 is a sectional view for illustrating a configuration
of a conventional vehicle lamp.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0061] Now, a lamp according to an embodiment of the presently
described subject matter will be described with reference to the
drawings.
[0062] FIG. 1 is a perspective view of a lamp according to an
embodiment of the presently described subject matter. FIG. 2 is an
exploded perspective view of components of the lamp shown in FIG.
1. FIG. 3 is an enlarged sectional view of the lamp shown in FIG.
1.
[0063] A lamp 100 of this embodiment can be applied to a vehicle
signal lamp such as a tail lamp, turn signal, and a general
illumination lamp other than a vehicle signal lamp, or the like.
The lamp 100 can include a first reflector 10, a second reflector
20, a plurality of first light sources 30, a plurality of inner
lenses 40, as shown in FIGS. 1 and 2.
[0064] First, the first reflector 10 will be described.
[0065] As shown in FIGS. 1 to 3, the first reflector 10 can include
a concave reflective surface 11 and a convex reflective surface
12.
[0066] The concave reflective surface 11 can be a concave mirror
(for example, a paraboloid of revolution) having, for example, a
substantially circular shape when viewed from the front, and a
predetermined depth D1 (for example, D1=15 mm. See FIG. 3). As
shown in FIG. 3, the convex reflective surface 12 can be a conical
reflective surface with a curved line C appearing to protrude
outwardly (or a straight line) when cut along a plane passing
through a vertex V1 and a lamp optical axis AX (centerline).
Alternatively, the reflective surface can appear as a straight
line, instead of as a curved line, when viewed in this
cross-section. The convex reflective surface 12 can be adjacent the
center of a bottom of the concave reflective surface 11, as shown
in FIG. 1. The shape of the convex reflective surface 12 can be
determined as described later, for example, using an existing
computer program.
[0067] Next, the second reflector 20 will be described.
[0068] As shown in FIGS. 2 and 3, the second reflector 20 can
include a first reflective surface 21 and a second reflective
surface 22.
[0069] As shown in FIG. 3, the first reflective surface 21 can
reflect an irradiation light L1 incident from the first light
source 30 toward the inner lens 40 corresponding with the
respective first reflective surface 21. The first reflective
surface 21 can be placed, for example, adjacent to a bottom surface
of the second reflector 20. The first reflective surface 21 can be
a paraboloid of revolution obtained by, for example, rotating a
parabola having a focus positioned at or adjacent to the first
light source 30 around the lamp optical axis AX.
[0070] As shown in FIG. 3, the second reflective surface 22 can
reflect an irradiation light L2 incident from the first light
source 30 toward the convex reflective surface 12 via the inner
lens 40 corresponding with the respective second reflective surface
22. The second reflective surface 22 can be arranged, for example,
on an inner side surface of the second reflector 20.
[0071] Next, the first light source 30 will be described.
[0072] The first light source 30 can be, for example, an LED light
source such as an LED package including one or more LED chips
(monochrome or three color RGB) in a package, or a bulb light
source such as an incandescent light bulb. When the first light
source 30 is an LED light sources, for example, the first light
sources 30 can be annularly arranged between the first reflector 10
and the second reflector 20 with their respective optical axis
(illumination direction) AX2 directed outward along a radial
direction of the lamp 100 with respect to the center of the lamp
100, as shown in FIG. 2.
[0073] Next, the inner lens 40 will be described.
[0074] The inner lens 40 can be a light illumination unit which can
receive the irradiation light from the first light source 30 and
can transmit the light incident thereon. The inner lens 40 can be,
for example, integrally manufactured by injection molding a
transparent or translucent material such as acryl or polycarbonate.
The inner lens 40 can have a surface subjected to a diffusion
process such as embossing. The inner lens 40 can include, for
example, as shown in FIG. 1, an acute-angled end 40a and an end 40b
on the opposite side of the acute-angled end 40a. The inner lenses
40 can be annularly arranged on the concave reflective surface 11
around the convex reflective surface 12 so as to be projected on
the convex reflective surface 12. Specifically, as shown in FIG. 1,
the inner lenses 40 can be inserted into openings H formed in the
concave reflective surface 11 so that the acute-angled end 40a can
be located closer to an outer peripheral edge 11e of the concave
reflective surface 11, and the end 40b on the opposite side can be
located closer to the center of the bottom of the concave
reflective surface 11. And, the inner lenses 40 can be placed
substantially at circumferentially regular intervals.
[0075] Next, a method of determining the convex reflective surface
12 will be described. The convex reflective surface 12 can be, for
example, determined using an existing computer program for an
optical design as described below.
[0076] FIGS. 4-7 illustrate the method of calculating the shape of
the convex reflective surface 12. FIGS. 4-7 show the shape of a
pattern P1 formed by a virtual image projected on the convex
reflective surface 12 calculated by the computer program for the
optical design.
[0077] First, as shown in FIG. 4, the shapes of the reflective
surfaces (such as the concave reflective surface 11 and the convex
reflective surface 12) can be determined, and the reflective
surfaces (such as the concave reflective surface 11 and the convex
reflective surface 12) and the inner lenses 40 can be arranged.
FIG. 4 shows an example in which a recessed mirror shape having a
predetermined depth D1 (for example, D1=15 mm, See FIG. 3) can be
used as the concave reflective surface 11, and a conical shape can
be used as the convex reflective surface 12.
[0078] Then, as shown in FIG. 5, the inner lenses 40 can be moved
toward the center of the bottom of the concave reflective surface
11 to adjust a pattern formed by a virtual image projected on the
convex reflective surface 12. Then, as shown in FIG. 6, a
comparatively high brightness portion A1 of each inner lens 40 can
be colored, for example, red, and the pattern P1 formed by the
virtual image projected on the convex reflective surface 12 can be
checked by an operator who manipulates the computer program or
reviews the calculation result of the computer program. Then, as
shown in FIG. 7, the convex reflective surface 12 can be curved
outwardly with respect to the center thereof so that the pattern P1
formed by the virtual image projected on the convex reflective
surface 12 becomes a desired size. Therefore, the pattern P1 formed
by the virtual image projected on the convex reflective surface 12
can be enlarged. As described above, the shape of the convex
reflective surface 12 on which the pattern P1 of the desired size
is formed can be determined. Thus, the convex reflective surface 12
can be formed, as shown in FIG. 3, as a conical reflective surface
with a curved line C protruding outwardly (or a straight line) with
respect to the center of the convex reflective surface 12 appearing
when cut along a plane passing through the vertex V1 of the convex
reflective surface 12 and the lamp optical axis AX
(centerline).
[0079] As described above, according to the lamp 100 of this
embodiment, as shown in FIG. 3, the convex reflective surface 12
can be formed as a conical convex reflective surface with the
curved line C appearing to protrude outwardly with respect to the
center of the convex reflective surface 12 when cut along the plane
passing through the vertex V1 and the lamp optical axis AX. Thus,
according to the lamp 100 of this embodiment, as shown in FIGS. 7
and 8, the plurality of inner lenses 40 can be projected on the
convex reflective surface 12 in a multiplexed manner, and the
virtual image projected on the convex reflective surface 12 can be
enlarged, and a pattern P1 with an appearance changing according to
viewpoint positions of an observer can be formed as shown in FIG.
9. Specifically, the number of the inner lenses 40 can appear to be
doubled as a result of the pattern P1. The pattern P1 can be
changed by changing the shape of the convex reflective surface
12.
[0080] Also, according to the lamp 100 of this embodiment, as shown
in FIG. 3, the irradiation light L1 emitted from the first light
source 30 and incident on the first reflective surface 21 can be
reflected by the first reflective surface 21, can pass through the
inner lens 40, can be irradiated in a direction indicated by L1 in
FIG. 3, and can form a first light distribution pattern
(particularly a light distribution pattern suitable for a vehicle
signal lamp). Also, according to the lamp 100 of this embodiment,
the irradiation light L2 emitted from the first light source 30 and
incident on the second reflective surface 22 can be reflected by
the second reflective surface 22, can pass through the inner lens
40, and can reach the convex reflective surface 12. The irradiation
light L2 incident on the convex reflective surface 12 can be
further reflected by the convex reflective surface 12 in a
direction indicated by L2 in FIG. 3, and can form a second light
distribution pattern (particularly a light distribution pattern
suitable for a wide vehicle signal lamp enlarged by the convex
reflective surface 12) superimposed on the first light distribution
pattern.
[0081] Specifically, according to the lamp 100 of this embodiment,
as shown in FIGS. 8 and 9, a lamp can be provided that can form a
pattern P1 with an appearance changing according to the viewpoint
positions of the observer, can form a predetermined light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp), and can have a new light
emission appearance.
[0082] Also, according to the lamp 100 of this embodiment, as shown
in FIG. 1, the acute-angled end 40a of the inner lens 40 can be
located closer to the outer peripheral edge 11e of the concave
reflective surface 11, and thus as shown in FIGS. 8 and 9, the
acute-angled end 40a of the inner lens 40 can be projected adjacent
to a tip portion (in the vicinity of the vertex V1) of the convex
reflective surface 12. Thus, a virtual image having a very sharp
shape can be enlarged. The pattern P1 formed on the convex
reflective surface 12 can form an appearance that significantly
changes by slight movement of an observer's eyes.
[0083] Specifically, according to the lamp 100 of this embodiment,
a lamp can be provided that can form a pattern P1 with an
appearance significantly changing by slight movement of eyes of the
observer, can form a predetermined light distribution pattern
(particularly a light distribution pattern suitable for a vehicle
signal lamp), and can have a new light emission appearance
(combination of a new appearance and a predetermined light
distribution pattern).
[0084] Next, Modified Example 1 will be described.
[0085] In the above-described embodiment, the example in which the
inner lenses 40 are annularly arranged on the concave reflective
surface 11 around the convex reflective surface 12 (see FIG. 1) has
been described, but the presently described subject matter is not
limited thereto.
[0086] For example, as shown in FIGS. 10, 12 and 14, the first
light sources 30 can be annularly arranged on the concave
reflective surface 11 around the convex reflective surface 12.
FIGS. 11, 13 and 15 show patterns formed by the annularly arranged
first light sources 30 being projected on the convex reflective
surface 12 shown in FIGS. 10, 12 and 14, respectively. Each pattern
shown in FIGS. 11, 13 and 15 changes its appearance according to
viewpoint positions of an observer. The first light sources 30 can
be projected on the convex reflective surface 12. Reference numeral
30' in the FIGS. 11, 13 and 15 represents the projected image of
the first light sources 30. The number of the first light sources
30 can appear to be doubled. The pattern can be changed by changing
the shape of the convex reflective surface 12.
[0087] Modified Example 1 can also provide a lamp which can form a
pattern with an appearance changing according to the viewpoint
positions of an observer, can form a predetermined light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp), and can have a new light
emission appearance.
[0088] Next, Modified Example 2 will be described.
[0089] In the above-described embodiment, the example in which the
convex reflective surface 12 is formed as the conical reflective
surface has been described (see FIGS. 1 and 3), but the presently
described subject matter is not limited thereto. For example, as
shown in FIGS. 12 and 14, the convex reflective surface 12 can be
formed as a polygonal pyramidal reflective surface. Even when the
convex reflective surface 12 has a polygonal pyramidal shape as in
FIGS. 12 and 14, the convex reflective surface 12 can be determined
by the same determination method of the convex reflective surface
12 as described in the above-described embodiment.
[0090] Modified Example 2 can also provide a lamp which can form a
pattern with an appearance changing according to the viewpoint
positions of an observer, can form a predetermined light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp), and can have a new light
emission appearance.
[0091] Next, Modified Example 3 will be described.
[0092] FIG. 16 is a perspective view of the lamp (Modified Example
3) according to another embodiment of the presently described
subject matter. FIG. 17 is an enlarged sectional view of a lamp 100
along line 17-17 shown in FIG. 16.
[0093] As shown in FIG. 17, Modified Example 3 is an example in
which an optical system 50 is added to the lamp 100 of FIG. 3
described above.
[0094] The optical system 50 can include a third reflective surface
51, a plurality of second light sources 52, and the convex
reflective surface 12.
[0095] The third reflective surface 51 can reflect an irradiation
light L3 incident from a second light source 52 toward the convex
reflective surface 12. The third reflective surface 51 can be, for
example, formed on the second reflector 20 in an integrated
fashion. The third reflective surface 51 can be, for example, a
paraboloid of revolution obtained by rotating a parabola having a
focus positioned at or adjacent the second light source 52 around
the lamp optical axis AX.
[0096] The convex reflective surface 12 can be a conical (or
polygonal pyramidal) reflective surface with a curved line C that
can appear to protrude outwardly with respect to the center thereof
(or a straight line) when cut along a plane through the vertex V1
and the optical axis AX (centerline). Alternatively, the conical
(or polygonal pyramidal) reflective surface can appear as a
straight line, instead of as a curved line, when viewed in this
cross-section. The convex reflective surface 12, for example, can
be formed as a reflective surface through which the light reflected
from the third reflective surface 51 and incident on the convex
reflective surface 12 can pass. The convex reflective surface 12
can be made by performing vapor deposition of metal such as
aluminum on a front or back surface of a conical (or polygonal
pyramidal) transparent member (for example, acryl or
polycarbonate). The convex reflective surface 12 can be, for
example, fixed to an opening periphery 11a formed at the center of
the bottom of the concave reflective surface 11 by any known fixing
device, such as threaded fastener, etc.
[0097] The second light source 52 can be, for example, an LED light
source such as an LED package including one or more LED chips
(monochrome or three color RGB) in a package, or a bulb light
source such as an incandescent light bulb. When the second light
sources 52 are LED light sources, for example, the second light
sources 52 can be annularly arranged with an optical axis
(illumination direction) directed inwardly with respect to the
center of the convex reflective surface 12 as shown in FIG. 17.
[0098] As shown in FIG. 16, the inner lens 40 can be formed to be
radially wider than the inner lens 40 described in the
above-described embodiment illustrated in FIG. 1 to increase an
amount of light.
[0099] Modified Example 3 can provide a lamp which can form a
pattern with an appearance changing according to viewpoint
positions of an observer, can form a predetermined light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp), and can have a new light
emission appearance.
[0100] Also, according to the lamp 100 of Modified Example 3, the
convex reflective surface 12 can be formed as the reflective
surface through which the light reflected from the third reflective
surface 51 and incident on the convex reflective surface 12 can
pass. Thus, as shown in FIG. 17, the irradiation light L3 from the
second light source 52 incident on the third reflective surface 51
can be reflected by the third reflective surface 51, can pass
through the convex reflective surface 12, can be irradiated in a
direction indicated by L3 in FIG. 17, and can form a third light
distribution pattern (particularly a light distribution pattern
suitable for a vehicle signal lamp) superimposed on the first and
second light distribution patterns.
[0101] Specifically, according to the lamp 100 of Modified Example
3, the third light distribution pattern formed by the irradiation
light L3 (see FIG. 17) from the second light source 52 can be
provided in addition to the first and second light distribution
patterns formed by the irradiation lights L1 and L2 (see FIGS. 3
and 17) from the first light source 30.
[0102] Thus, for example, when the lamp 100 of Modified Example 3
is applied to a tail lamp of a vehicle, for example, the light
sources 30 and 52 can be controlled so that, for example, only the
first light source 30 is turned on when a brake of the vehicle is
not applied, and both the first light source 30 and the second
light source 52 are turned on when the brake is applied. Thus, a
sufficient amount of light can be ensured even when the brake is
applied. Therefore, the lamp 100 of Modified Example 3 can allow
formation of a light distribution pattern which can satisfy a
government standard.
[0103] The above-described embodiments are just some of the
examples of the presently disclosed subject matter. The scope of
the presently described subject matter should not be restrictively
construed by these embodiments and examples. The presently
described subject matter can be carried out in various ways without
departing from the spirit and main features thereof.
[0104] While there has been described what are at present
considered to be exemplary embodiments of the invention, it will be
understood that various modifications may be made thereto, and it
is intended that the appended claims cover such modifications as
fall within the true spirit and scope of the invention. All
conventional art references described above along with any English
translations thereof are herein incorporated in their entirety by
reference.
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